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1.
Math Biosci Eng ; 20(9): 17018-17036, 2023 08 29.
Artículo en Inglés | MEDLINE | ID: mdl-37920045

RESUMEN

Sleep plays an important role in neonatal brain and physical development, making its detection and characterization important for assessing early-stage development. In this study, we propose an automatic and computationally efficient algorithm to detect neonatal quiet sleep (QS) using a convolutional neural network (CNN). Our study used 38-hours of electroencephalography (EEG) recordings, collected from 19 neonates at Fudan Children's Hospital in Shanghai, China (Approval No. (2020) 22). To train and test the CNN, we extracted 12 prominent time and frequency domain features from 9 bipolar EEG channels. The CNN architecture comprised two convolutional layers with pooling and rectified linear unit (ReLU) activation. Additionally, a smoothing filter was applied to hold the sleep stage for 3 minutes. Through performance testing, our proposed method achieved impressive results, with 94.07% accuracy, 89.70% sensitivity, 94.40% specificity, 79.82% F1-score and a 0.74 kappa coefficient when compared to human expert annotations. A notable advantage of our approach is its computational efficiency, with the entire training and testing process requiring only 7.97 seconds. The proposed algorithm has been validated using leave one subject out (LOSO) validation, which demonstrates its consistent performance across a diverse range of neonates. Our findings highlight the potential of our algorithm for real-time neonatal sleep stage classification, offering a fast and cost-effective solution. This research opens avenues for further investigations in early-stage development monitoring and the assessment of neonatal health.


Asunto(s)
Redes Neurales de la Computación , Sueño , Recién Nacido , Niño , Humanos , China , Fases del Sueño/fisiología , Algoritmos , Electroencefalografía
2.
Sci Rep ; 13(1): 14017, 2023 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-37640780

RESUMEN

This paper proposes a nature-inspired spider web-shaped ultra-high frequency (UHF) radio frequency identification (RFID) reader antenna and battery-free sensor-based system for healthcare applications. This antenna design consists of eight concentric decagons of various sizes and five straight microstrip lines.These lines are connected to the ground using 50 [Formula: see text] resistors from both ends, except for one microstrip line that is reserved for connecting a feeding port. The reader antenna design features fairly strong and uniform electric and magnetic field characteristics. It also exhibits wideband characteristics, covering whole UHF RFID band (860-960 MHz) and providing a tag reading volume of 200 [Formula: see text] 200 [Formula: see text] 20 mm[Formula: see text]. Additionally, it has low gain characteristics, which are necessary for the majority of nearfield applications to prevent the misreading of other tags. Moreover, the current distribution in this design is symmetric throughout the structure, effectively resolving orientation sensitivity issues commonly encountered in low-cost linearly polarized tag antennas. The measurement results show that the reader antenna can read medicine pills tagged using low-cost passive/battery-free RFID tags, tagged expensive jewelry, intervenes solution, and blood bags positioned in various orientations. As a result, the proposed reader antenna-based system is a strong contender for near-field RFID, healthcare, and IoT applications.


Asunto(s)
Dispositivo de Identificación por Radiofrecuencia , Arañas , Animales , Suministros de Energía Eléctrica , Electricidad , Instituciones de Salud
3.
Sensors (Basel) ; 22(20)2022 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-36298110

RESUMEN

In this paper, a novel embedded helix dielectric rod antenna is presented for high gain radiation with circular polarization (CP) and low side lobe levels for IoT Applications. Different from the conventional dielectric rod antennas, this proposed antenna is an integrated structure that combines the advantages of the helix and dielectric rod antennas. The presented antenna mainly consists of three parts: a tapered helix as primary feeding for CP, a dielectric rod with printed loops embedded for higher directivity, and a dielectric rod end for improving the gain further. After studying and analyzing the working principles of each part, an optimum design operating at 8-9.7 GHz is carried out as an example. A prototype is also fabricated and tested. The measured results show that the prototype can provide 18.41 dB maximum gain within the length of 7.7 λ. The side lobe level is below -20 dB, and the axial ratio is better than 1.14 dB in the whole frequency band. Compared with the traditional helix antenna and dielectric rod antenna with the same electric length, the presented antenna has a higher gain with a lower side lobe level and with good polarization purity.


Asunto(s)
Electricidad , Tecnología Inalámbrica , Diseño de Equipo , Refracción Ocular
4.
Big Data ; 2022 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-35377193

RESUMEN

Wireless in vivo actuators and sensors are examples of sophisticated technologies. Another breakthrough is the use of in vivo wireless medical devices, which provide scalable and cost-effective solutions for wearable device integration. In vivo wireless body area networks devices reduce surgery invasiveness and provide continuous health monitoring. Also, patient data may be collected over a long period of time. Given the large fading in in vivo channels due to the signal path going through flesh, bones, skins, and blood, channel coding is considered a solution for increasing the efficiency and overcoming inter-symbol interference in wireless communications. Simulations are performed by using 50 MHz bandwidth at Ultra-Wideband frequencies (3.10-10.60 GHz). Optimal channel coding (Turbo codes, Convolutional codes, with the help of polar codes) improves data transmission performance over the in vivo channel in this research. Moreover, the results reveal that turbo codes outperform polar and convolutional codes in terms of bit error rate. Other approaches perform similarly when the information block length is increased. The simulation in this work indicates that the in vivo channel shows less performance than the Rayleigh channel due to the dense structure of the human body (flesh, skins, blood, bones, muscles, and fat).

5.
Math Biosci Eng ; 19(1): 792-811, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34903013

RESUMEN

Wireless body area networks (WBANs) is a new research hotspot with great development prospects. The non-contact sensing based on radio frequency signal can solve the issues of personal comfort and privacy. Detection of cervical motion range and cervical strain in time are important in diagnosis and prevention of cervical spondylosis. In this paper, channel state information is used to achieve smart perception and monitoring, timely and efficient detection of different postures and abnormal bending of the neck. It provides an efficient way for protecting cervical health, and also some help for doctors to understand the causes of cervical vertebral disease in a timely manner. The classification accuracy of the four activities reached 99.4%, 99.7%, 99.5% and 99.3%, respectively.


Asunto(s)
Espondilosis , Vértebras Cervicales , Humanos , Cuello , Espondilosis/diagnóstico
6.
Micromachines (Basel) ; 12(9)2021 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-34577672

RESUMEN

Micro-/nano-scaled structures, materials, and devices enable the continuous monitoring of human physical activities and behaviors, as well as physiological and biochemical parameters during daily life [...].

7.
Sensors (Basel) ; 20(9)2020 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-32380656

RESUMEN

Information and Communication Technology (ICT) enabled optimisation of train's passenger traffic flows is a key consideration of transportation under Smart City planning (SCP). Traditional mobility prediction based optimisation and encryption approaches are reactive in nature; however, Artificial Intelligence (AI) driven proactive solutions are required for near real-time optimisation. Leveraging the historical passenger data recorded via Radio Frequency Identification (RFID) sensors installed at the train stations, mobility prediction models can be developed to support and improve the railway operational performance vis-a-vis 5G and beyond. In this paper we have analysed the passenger traffic flows based on an Access, Egress and Interchange (AEI) framework to support train infrastructure against congestion, accidents, overloading carriages and maintenance. This paper predominantly focuses on developing passenger flow predictions using Machine Learning (ML) along with a novel encryption model that is capable of handling the heavy passenger traffic flow in real-time. We have compared and reported the performance of various ML driven flow prediction models using real-world passenger flow data obtained from London Underground and Overground (LUO). Extensive spatio-temporal simulations leveraging realistic mobility prediction models show that an AEI framework can achieve 91.17% prediction accuracy along with secure and light-weight encryption capabilities. Security parameters such as correlation coefficient (<0.01), entropy (>7.70), number of pixel change rate (>99%), unified average change intensity (>33), contrast (>10), homogeneity (<0.3) and energy (<0.01) prove the efficacy of the proposed encryption scheme.

8.
Healthc Technol Lett ; 4(6): 244-248, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29383259

RESUMEN

In our daily life, inadvertent scratching may increase the severity of skin diseases (such as atopic dermatitis etc.). However, people rarely pay attention to this matter, so the known measurement behaviour of the movement is also very little. Nevertheless, the behaviour and frequency of scratching represent the degree of itching, and the analysis of scratching frequency is helpful to the doctor's clinical dosage. In this Letter, a novel system is proposed to monitor the scratching motion of a sleeping human body at night. The core device of the system is just a leaky coaxial cable (LCX) and a router. Commonly, LCX is used in the blind field or semi-blindfield in wireless communication. The new idea is that the leaky cable is placed on the bed, and then the state information of physical layer of wireless communication channels is acquired to identify the scratching motion and other small body movements in the human sleep process. The results show that it can be used to detect the movement and its duration. Channel state information (CSI) packet is collected by card installed in the computer based on the 802.11n protocol. The characterisation of the scratch motion in the collected CSI is unique, so it can be distinguished from the wireless channel amplitude variation trend.

9.
Healthc Technol Lett ; 2(3): 74-7, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26609409

RESUMEN

With the aim of reducing cost and power consumption of the receiving terminal, compressive sensing (CS) framework is applied to on-body ultra-wideband (UWB) channel estimation. It is demonstrated in this Letter that the sparse on-body UWB channel impulse response recovered by the CS framework fits the original sparse channel well; thus, on-body channel estimation can be achieved using low-speed sampling devices.

10.
IEEE J Biomed Health Inform ; 19(3): 858-65, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25014979

RESUMEN

Parametric probability models are common references for channel characterization. However, the limited number of samples and uncertainty of the propagation scenario affect the characterization accuracy of parametric models for body area networks. In this paper, we propose a sparse nonparametric probability model for body area wireless channel characterization. The path loss and root-mean-square delay, which are significant wireless channel parameters, can be learned from this nonparametric model. A comparison with available parametric models shows that the proposed model is very feasible for the body area propagation environment and can be seen as a significant supplement to parametric approaches.


Asunto(s)
Redes de Comunicación de Computadores , Monitoreo Fisiológico/métodos , Ondas de Radio , Humanos , Análisis de Regresión , Estadísticas no Paramétricas , Máquina de Vectores de Soporte
11.
IEEE Trans Inf Technol Biomed ; 16(2): 221-7, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22147331

RESUMEN

The paper presents a subject-specific radio propagation study and system modeling in wireless body area networks using a simulation tool based on the parallel finite-difference time-domain technique. This technique is well suited to model the radio propagation around complex, inhomogeneous objects such as the human body. The impact of different digital phantoms in on-body radio channel and system performance was studied. Simulations were performed at the frequency of 3-10 GHz considering a typical hospital environment, and were validated by on-site measurements with reasonably good agreement. The analysis demonstrated that the characteristics of the on-body radio channel and system performance are subject-specific and are associated with human genders, height, and body mass index. Maximum variations of almost 18.51% are observed in path loss exponent due to change of subject, which gives variations of above 50% in system bit error rate performance. Therefore, careful consideration of subject-specific parameters are necessary for achieving energy efficient and reliable radio links and system performance for body-centric wireless network.


Asunto(s)
Tecnología de Sensores Remotos , Tecnología Inalámbrica , Adulto , Índice de Masa Corporal , Simulación por Computador , Femenino , Humanos , Masculino , Modelos Biológicos , Fantasmas de Imagen , Ondas de Radio , Reproducibilidad de los Resultados , Telemedicina
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